nb/intel: Don't select VBOOT_SEPARATE_VERSTAGE

Now the bootblock is not limited to 64K so integrating vboot into the
bootblock reduces the binary size.

Change-Id: Ic92ecf8068f327a893d20924685ce571752d379f
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52787
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/emulation/qemu-i440fx/Kconfig

@@ -19,7 +19,6 @@ config BOARD_SPECIFIC_OPTIONS
 config VBOOT
 	select VBOOT_MUST_REQUEST_DISPLAY
 	select VBOOT_STARTS_IN_BOOTBLOCK
-	select VBOOT_SEPARATE_VERSTAGE
 	select VBOOT_VBNV_CMOS
 	select VBOOT_NO_BOARD_SUPPORT
 	select GBB_FLAG_DISABLE_LID_SHUTDOWN